ᐅ Forgot to install perimeter insulation

As mentioned above:
We withheld the final installment (the third one) due to defects.

And how high were the paid installments?

Once 2.38%
And once 10%

Are the foundation slab and ground floor already completed? How can there be so many points of disagreement at this stage? Perhaps the withheld payment and insolvency are related?

Why argue? The defects are undisputed!!

Of course, the insolvency is related to the fact that the clients did not pay. If their buildings are only half as botched as ours, I’m surprised they managed to survive for 5 years at all!!

I have read all 10 pages. It is really hard to understand who is who and where. People use clear terms like developer, general contractor, and construction company, then two pages later they change their meaning again. That doesn’t work.

Since you own your land, a developer can’t be involved here (developers sell the finished house with land).
So what exactly is a general contractor and what is a construction company? Aren’t they basically the same at first?

Who do you have a contract with? Most likely a general contractor, from whom you ordered a “turnkey” house.
The general contractor hired a subcontractor — a construction company — who took on the masonry work.

The general contractor with whom you ordered the turnkey house has now filed for bankruptcy?

Is that all correct so far?

One good thing is that you basically haven’t paid anything yet for your shell construction. The floor slab didn’t come, of course, because the general contractor didn’t pay for the previous slabs (bankruptcy). The payment plan has been very accommodating to you here; otherwise, you would have paid a lot more.
With the serious defects, the work already done isn’t really worth much. However, you already know that you can insulate the foundation slab from above. I would still recommend proactively raising the ceiling height of the upper floor. In the very unlikely case that you don’t need the extra height, you gain more ceiling space later. But if you do need that extra height, you would end up living in a cave. At this point, that’s a joke.

What’s much more important, though, is how you get out of the contract with the bankrupt general contractor. The insolvency administrator will probably want to collect money for the work already done. Whether they will release you from the contract and/or require defect repairs or prolong the whole process is something your lawyer can best explain to you.
The best outcome would probably be to get out of it quickly (without fixing defects) and not pay a cent for the poor workmanship.

Then you can either hire each trade yourself or look for another company to finish the job. Neither option is easy, because obviously no one wants to take responsibility or guarantee work for the current botched work — after all, it’s the foundation of the house.

You need a proper expert, specialized in foundations/floor slabs. Whoever skips the perimeter insulation might have made other mistakes as well...